The heart is the center of a person's circulatory system. The left portions of the heart, including the left atrium (LA) and left ventricle (LV), draw oxygenated blood from the lungs and pump it to the organs of the body to provide the organs with their metabolic needs for oxygen. The right portions of the heart, including the right atrium (RA) and right ventricle (RV), draw deoxygenated blood from the body organs and pump it to the lungs where the blood gets oxygenated. Heart failure occurs when the heart fails to pump sufficient blood to supply the organs with their metabolic needs for oxygen. The insufficiency of blood supply to the kidneys may impair renal function to the extent causing excessive fluid retention in the body, known as decompensation.
Drugs such as diuretics are used to treat decompensation. Diuretics increases removal of liquid from the body by increasing urinary flow. A known side effect associated with excessive dose of diuretics is hypovolemia, or decreased circulatory blood volume. Other causes of hypovolemia include dehydration and bleeding. The symptoms of hypovolemia include dizziness, nausea, and extreme thirst. Hypovolemia may develop into a hypovolemic shock, in which the heart is unable to supply enough blood to the body due to the low circulatory blood volume, causing organs of the body to fail.
To manage a treatment of decompensation for heart failure patients, such as a drug therapy using diuretics, there is a need to monitor for hypovolemia.